Collapsible core



March 15, 1938. J, A, CRAVEN COLLAPSIBLE coma Filed July 24, 1936 //V VE N TUE- JA Y A GRAVE N.

his ATTUENEK ail!!!Illlllilllllllllilllfftrflllllllfflllfillflllllli M NE E P mg Patented Mar. 1 5, 1938 2 111 UNITED STATES FATET OFFEQ 2,111,063 coLLArsIBLE CORE Jay A. Craven, Dayton, Ohio Application July 24, 1936, Serial No; 92,413 4 Claims. (01. 25-131) This invention relates to a collapsible core for cores showing the complete separation of the two use in the construction of hollow concrete strucparts of the wall; Fig. '7 is a sectional detail view tures and it is designed more particularly for use of a portion of such a concrete wall showing the in the construction of ahollow concrete wall. In inwardly extending fins formed between the cores;

5 the construction of hollow concrete walls an and Fig. 8 is a plan view of the guide for the 5 inner form isarranged between and spaced from actuating member. the side members of the outer form and inasmuch In the drawing I have illustrated one embodias it is not usually practical to make this inner ment of my invention and I have shown the same form of a length equal to the length of the wall as comprising parallel side members or walls i9 10 it is customary to use a plurality of collapsible which are connected at their ends by end memll cores or sections which are arranged end to end bers or walls, each of which end members has a between the side members of the outer form. The part which is movable inwardly with relation to two-parts of the hollow wallshould have no conthe side members in such a manner as to draw the crete connection between them but are connected side members one toward the other and thus col- 5 to the other y by me a lic/tie bars, there lapse the core. In the particular construction being usually a plurality of series of such tie bars, shown each end member comprises two longithe bars of each series being arranged one above tudinal parts H which are pivotally connected t oth in Sp e n- The j nt en one to the other and with the adjacent edges of of the cores of the inner form ab t a t h the respective side-members. Preferably each Oppo Sides of the respective tie bars" arid this part H of the end member is provided with hinge 20 necessarily results in the ends of the cores being bearings t receive hinge pins lg,

spaced short distances one from the other. The Arranged between the side members iii is an cores heretofore used have been of such a charactuating device which is so connected with the acter that the soft'concretewould enter the space respective end members that it will impart inbetween adjacent cores, above and below the tie ward or outward movement to said members and 25 ars, a d would s fill thiS Space t0 fOIm a thus collapse or expand the core. Preferably this concrete tie between the two parts of the wall actuating device comprises a longitudinally movwhich is highly objectionable because it permits able member is which is connected with the end of the transmission of moisture from the outer members by links 54 each of which is pivotally part of the wall to the inner part thereof. connected at one end to the actuating member 30 One object of the present invention is to prol3 and pivotallyconnected at its other end to a vide acollapsible core which will be of simple in- U-shaped lug it which extends about the pivot expensive construction and can be easily colpin 12 which connects the two parts of the end lapsed, member one to the other. The links and the A-further object of the invention is to provide actuating member function as a toggleand when such a core which will have no overlapping parts the actuating member is moved downwardly the slidable one upon the other. links will extend the end members thus forcing A--further object of the invention is to provide the side members to their outermost positions. a'collapsible core of such a character that the If the two links are moved into'alinement one spacesbetween adjacent cores, above and below with the other the-core will be positively locked 40 the tie bars, will not be filled with concrete, thus in its extended position, but it is sometimes deavoiding any connection between the two parts sirable to move the end members outwardly slightof the hollow wall other than the metallic tie bars. ly beyond their normal extended positions and I Other objects of the invention may appear as have provided means for retaining the core memthe device is described in detail. I bers intheir normal extended positions without 45 In the accompanying drawing Fig. 1 is a plan fully extending the links, as will hereinafter apview of a collapsible core embodying my invenpear, The upward movement of the actuating tion; Fig. 2-isa side elevation of the same, partly member will move the connected edges of the two in section; Fig. 3 is an end View of such a core, parts of each end wall inwardly, thus drawing the partly in section; Fig. 4 isa sectional detail view side members inwardlytothe positions shown in 50 'of a-portion of the core; Fig. 5 is a horizontal dotted lines in Fig.4, thereby simultaneously movsectional view taken through a concrete wall ing the four core members out of contact with showing portions of two cores in position inthe the concrete wall. The actuating member may wall; Fig. 6 isa vertical section of a portion of be manipulated in any suitable manner but I 5.1 awall which has been formed with'my collapsible prefer to provide a screw for actuating the same,

and, as here shown, a nut i6 is rigidly secured to a supporting member or plate ll which is carried by the side members of the core and is slidably connected therewith, as by means of the metallic clips 18, so that the side members may have movement with relation to the supporting member ll. Rotatably mounted in this nut is a screw E9 the lower end of which has swiveled connection with the upper end of the actuating member 13, is shown at 29, so that the screw may rotate with relation to the actuating member but the actuating member will move vertically with the screw. Any suitable means may be provided for rotating the screw and, as here shown, the upper end of the screw is squared to receive a socket Wrench or the like. The pitch of the screw thread is sufiiciently low to render the screw self-locking so that the core members will be automatically secured in any position to which they may be moved.

If desired telescoping guide members 2! and 22 may be rigidly secured to the inner surfaces of the side members to maintain the same in their proper relative positions and, if desired, the side members may be reinforced, as by means of angle bars 23. It may also be desirable to provide a guide to retain the actuating member E3 in an approximate vertical position and thus cause substantially equal movements to be imparted to the two end members. As here shown overlapping guide plates 32 are secured to the respective side members and provided with registering apertures to receive the actuating member. The apertures are of such size and shape as to prevent any ap-- preciable movement of the actuating member lengthwise of the core, that is, toward either end member, but to permit the guide plates to move with relation to the actuating member in a direction transverse to the core, so as not to interfere with the expansion and contraction of the core members.

In order to prevent the formation of a concrete tie between the two parts of the hollow wall each end member of the core is provided with outwardly extending vertical parts spaced one from the other to form between them a recess. In the present construction the two parts H of the end wall are curved outwardly about separate axes extending lengthwise thereof so that the intermediate or connected edges of these parts are spaced inwardly over the outermost surfaces thereof to form a substantially V-shaped recess. When the several cores constituting the inner form are placed in position between the side members of the outer form the adjacent ends of the cores will abut against the opposite sides of tie bars 24, as shown in Fig. 5. These tie bars are supported by the side members of the outer form and extend through and beyond said side members, the end portions of the tie bars being weakened, as shown at 25 in Fig. 6, to permit these end portions to be broken off after the concrete has set. When the two cores are in contact with the tie bar the recesses in the end members of the two cores will be in opposed relation so as to form between them a vertical chamber 26 which is of a width or diameter substantially greater than the thickness of the tie bars. When the soft concrete is poured into the forms it will enter the V-shaped spaces between the outer sides of the two cores but the coarse aggregate will quickly clog the narrow space between the outwardly curved portions of the end members I I so that little or no concrete will enter the chamber 26 and any small quantity of concrete which may enter that chamber will drop to the bottom of the chamber where it will do no harm. Consequently the intermediate space between the outwardly curved portions of the end members, which constitutes the chamber 26, will never be filled with concrete and there will be no concrete tie between the two parts of the concrete wall. The concrete which enters the V- shaped spaces at the sides of the cores will assume the shape shown in Fig. 7 but the fins 27 thus formed will terminate in the narrow spaces between the outwardly projecting curved portions of the end members so that the fins on the two parts of the concrete wall will be spaced a Very substantial distance one from the other, as shown in Fig. 6, where the concrete wall is indicated by the reference numeral 28.

The cores may be of any desired dimensions and will usually be made of a depth corresponding to that portion of the wall which can be formed by a single pouring of concrete. This depth will vary and it may be substantially greater than the length of the core. When one section of the wall has been poured and has set the cores are collapsed and moved upwardly in preparation for the pouring of another section of the wall, the lower end of each core remaining in the formed portion of the wall to properly locate the core with relation thereto. To facilitate this resetting of the core the side members may be provided near their lower ends with spurs 36 which will bite into the wall and temporarily support the core in its adjusted position. The side members may, if desired, be provided with means, such as apertured lugs 3!, for attaching a lifting device to the core, to facilitate the handling of the same.

While I have shown and described one embodiment of my invention I wish it to be understood that I do not desire to be limited to the details thereof as various modifications may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A collapsible core for a concrete structure comprising side members and end members connecting the adjacent edges of said side members, each end member having two -longitudinal parts pivotally connected one to the other and to the edges of the respective side members, whereby the inward or outward movement of said end members will impart corresponding movement to said side members, an actuating member ar ranged between said side members and operatively connected with said end members, and an operating device having supporting connection with both side members and operatively connected with said actuating member to cause the latter to impart either outward or inward movement to said end members, the connection between said operating device and said side members being such as to permit the latter to move toward and from each other.

2. A collapsible core for a concrete structure comprising side members and end members connecting the adjacent edges of said side members, each end member having two longitudinal parts pivotally connected one to the other and to the edges of the respective side members, whereby the inward or outward movement of said end members will impart a corresponding movement to said side members, a vertically movable actuating member arranged between said side members, links pivotally connected with said actuating member and the respective end members, a supporting member mounted on said side members and slidably connected therewith to enable said side members to move toward and from each other, and a screw mounted on said supporting member for vertical movement with relation thereto and operatively connected with said actuating member.

3. A collapsible core for a concrete structure comprising side members and end members connecting the adjacent edges of said side members, each end member having two longitudinal parts pivotally connected one to the other and to the edges of the respective side members, whereby the inward or outward movement of said end members will impart a corresponding movement to said side members, a vertically movable actuating member arranged between said side members, links pivotally connected with said actuating member and the respective end members, an operating device supported by said coreand operatively connected with said actuating member to impart vertical movement thereto, and a guide for said actuating member arranged between said side members and acting on said actuating memher to hold the same against substantial transverse movement toward either end member.

4. A collapsible core for a concrete structure comprising side members and end members connecting the adjacent edges of said side members, each end member having two longitudinal parts pivotally connected one to the other and to the edges of the respective side members, whereby the inward or outward movement of said end membars will impart a corresponding movement to said side members, a vertically movable actuating member arranged between said side members, links pivotally connected with said actuating member and the respective end members, an operating device supported on said side walls and operatively connected with said actuating member to impart vertical movement thereto, and guide members carried by and movable with the. respective side members and having alined openings through which said actuating member extends, said openings being shaped to permit said side members to move toward and from said actuating member and to hold the latter against substantial movement toward either end member.

JAY A. CRAVEN. 

